This study will provide information on the manner in which ethanol acts to alter electrical activity in the nervous system. In particular, slow steadystate membrane currents which are altered by ethanol will be examined. These currents underlie bursting pacemaker activity, and their alteration will produce profound changes in the overall activity pattern within the nervous system. Previous voltage clamp examination of ethanol action has focused on effects upon action potential conductances. The effects to be examined in this study require lower ethanol concentrations than those necessary to significantly alter the action potential and may serve as a better model extrapolating to the neuronal basis of alcoholism in humans. A combination of electrophysiological, pharmacological and fluorescence techniques will be used in a molluscan model system. The molecular basis for ethanol action, and possibly the molecular basis for phenomena such as ethanol tolerance, can be approached by these methods. It is expected that the type of information obtained from this study will prove useful in formulating rational approaches to treatment and prevention of alcoholism, as well as providing a basic understanding of how nerve cells function.